\(A\) 10 W electric heater is used to heat a container filled with \(0.5 \mathrm{kg}\) of water. It is found that the temperature of water and the container rises by \(3^{\circ} \mathrm{K}\) in \(15 \mathrm{min}\). The container is then emptied, dried and filled with \(2 \mathrm{kg}\) of oil. The same heater now raises the temperature of container-oil system by \(2^{\circ} \mathrm{K}\) in \(20 \mathrm{min}\). Assuming that there is no heat loss in the process and the specific heat of water is \(4200 \mathrm{d} \mathrm{kg}^{-1} \mathrm{K}^{-1}\), the specific heat of oil in the same unit is equal to

1. A \(1.50 \times 10^{3}\)
2. B \(2.55 \times 10^{3}\)
3. C \(3.00 \times 10^{3}\)
4. D \(5.10 \times 10^{3}\)